Influence of the AS-Printing and Post-Printing Processes on the Mechanical Properties of Liquid Metal Jetted 3D Parts

Abstract

Heat treatable aluminum alloys require post-fabrication steps to achieve the desired properties. The conditions to treat cast aluminum parts are well established, however the same processes are not well studied for additive manufactured (AM) parts. This study evaluated the effects of post-printing processes on the hardness of metal parts fabricated by AM. The research focused on the intermediate period from print completion to immersion of the sample into the quenching bath and how delays can influence the parts hardness. Those results were compared to samples that were then solution treated. Aging procedures were conducted to evaluate the influence of diverse time and temperature on hardness. In addition to post-printing process studies, an experiment was conducted to evaluate the effects of introducing additional argon into the printing environment as the 3D part is produced. It was found that quenching after the initial minute of print completion has lasting effects on hardness that are not reversed by the solution treatment step at the temperatures and times employed. Modifying the standard aging time and temperature by plus/minus 15 deg C or plus/minus 20 minutes did not show a significant effect on the mechanical properties of the prints (less than 3 percent change in hardness). Samples that were heat treated increased in hardness, demonstrating the usefulness of the T6 heat treatment. The 3D printer was employed to fabricate the component used to distribute extra argon into the printing environment.

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Document Details

Document Type
Technical Report
Publication Date
Jun 01, 2022
Accession Number
AD1184968

Entities

People

  • Kahra L Kelty

Organizations

  • Naval Postgraduate School

Tags

Communities of Interest

  • Advanced Electronics
  • Biomedical
  • Ground and Sea Platforms

DTIC Thesaurus Topics

  • Additive Manufacturing
  • Aluminum
  • Aluminum Alloys
  • Computer-Aided Design
  • Electron Microscopy
  • Fabrication
  • Hardness
  • Manufacturing
  • Materials
  • Materials Engineering
  • Materials Processing
  • Materials Science
  • Mechanical Properties
  • Mechanical Working
  • Particle Size
  • Phase Diagrams
  • Scanning Electron Microscopy
  • Selective Laser Sintering
  • Solid Solutions
  • Standards
  • Tensile Strength
  • Tensile Testing
  • United States Naval Academy

Fields of Study

  • Materials science

Readers

  • Manufacturing Engineering.
  • Powder metallurgy of Titanium alloys.
  • Thermal Physics or Thermal Science.